1. Field of the Invention
The present invention relates to a foldable front wheel of a golf cart, more particularly one, which can be securely held in stretched position for allowing the golf cart to move along smoothly, and can be easily unlocked and smoothly moved between the stretched position and the folded position without possibility of causing damage to the folding mechanism provided thereto.
2. Brief Description of the Prior Art
Referring to FIG. 1, a conventional folding golf cart 1 includes a frame 11, a handle 12 pivoted to an upper end of the frame 11, two rear wheel supports 13 pivoted to a middle portion of the frame 11, rear wheels 14 respectively connected with the rear wheel supports 13, two connecting rods 15, a lower support 16 secured on the frame 11 for supporting a golf bag on, a pivotal mechanism 17 connected with the frame 11, a front wheel support 19, and a front wheel 18 fitted to the front wheel support 19.
The pivotal mechanism 17 includes a middle pivotal body 171, a pairs of lateral pivotal bodies 172, a bolt 174, and a knob 175; the lateral pivotal bodies 172 have engaging toothed sides 1722, and fitting holes 1721, and are respectively securely joined to lower ends of rod portions of the frame 11 with the lower ends of the frame 11 being passed into the fitting holes 1721, and with the engaging toothed sides 1722 facing each other; the bolt 174 is passed through both of the lateral pivotal bodies 172, and screwed into the knob 175 at a tail end; the middle pivotal body 171 has engaging toothed sides 1711 on two ends, and is arranged between the lateral pivotal bodies 172, and pivoted on the bolt 174 such that it is angularly displaceable relative to the frame 11, and such that the toothed sides 1711 facing respective ones of the toothed sides 1722.
The front wheel support 19 is securely joined to the middle pivotal body 171 to be movable together with the pivotal body 171. Therefore, when the knob 175 is screwed to a tight position, the lateral bodies 172 will be engaged with the middle pivotal body 171 at the toothed sides 1722, and in turns, the wheel support 19 can't move relative to the frame 11. And, when the knob 175 is screwed loose, the lateral bodies 172 will stop engaging the middle pivotal body 171, and in turns, the front wheel 18 can be changed in the orientation relative to the frame 11 together with the middle pivotal body 171. Thus, the front wheel 18 can be secured in a stretched position for use, and can be secured in a folded position when the golf cart 1 isn't used.
However, the pivotal mechanism 17 for the front wheel 18 is found to have disadvantages as followings:    1. Even though the knob 175 has been turned loose, the middle pivotal body 171 can be rubbed against the toothed sides 1722 at the toothed sides 1711 thereof while the front wheel 18 is being displaced relative to the frame 11. Consequently, the engaging toothed sides 1711 and 1722 will be damaged, and the front wheel 18 can't be secured in position any more.    2. The user can turn the knob 175 too much after changing the position of the front wheel 18, and in turns, screw threads of the knob 175 and the bolt 174 will get damaged.    3. The knob 175 can become loose owing to vibration of the golf cart, and in turns, the front wheel 18 will be away from the stretched position while the golf cart is being used.    4. It is difficult for the user to move the front wheel 18 to a same proper stretched position in every stretching action, and also difficult to move the front wheel 18 to a same folded position in every folding action because the golf cart isn't equipped with a mechanism that will stop the middle pivotal body 171 as soon as the front wheel 18 is moved to either of the proper positions.